In 2021, Scottsdale Water celebrated 50 years of providing quality drinking water and advanced reclamation services to Scottsdale businesses and residents. Through innovative technology, advanced planning, and commitment from local officials, residents and businesses, Scottsdale Water will continue to lead the industry into the future. Learn more about the history of Scottsdale Water!

Historical Timeline

To mark this milestone, Scottsdale Water looks back on historical events that led to today’s success.


The Hohokam people realized the need for an extensive water delivery system in order to support their growing population. They excavated extensive canals throughout the Salt River Valley in order to transport water for irrigation purposes. These canals extended for several 100 miles over the desert landscape and were up to 12-feet deep. The canals later became the foundation for the Salt River Project canals.


The Arizona Canal was completed after beginning in 1883, allowing farming to prosper in Scottsdale.


Salt River Valley Water Users’ Association organized on February 4, the first of its kind in the U.S. following passage of the National Reclamation Act.


Theodore Roosevelt Dam was completed at Tonto Basin. This provided Salt River water to the Salt River Valley. Begun in 1903, it was the Federal government’s first-ever reclamation project.


Arizona achieved statehood on Feb. 14, 1912.


Arcadia Water Company formed to serve Scottsdale.


The Colorado River Compact set up future allocations of Colorado River water to the Upper and Lower Basin States. Seven Colorado River basin states (Arizona, California, Nevada, Colorado, New Mexico, Utah and Wyoming) began negotiating for Colorado River water rights and in 1922 formed the Colorado River Compact. The states divided into Upper and Lower Basin states (Arizona is in the Lower Basin) and allocated 7.5 million acre-feet to each basin. Arizona disputed its share of the water allocation and didn’t approve the compact until 1944.


The Boulder Dam (later renamed Hoover Dam) was dedicated to provide Colorado River water to neighboring states.


The City of Phoenix purchased the Brown Water Company in unincorporated Scottsdale.


The Town of Scottsdale officially incorporated on June 25, 1951, with 2,032 people living within an approximately half-mile municipal boundary.


Town of Scottsdale dedicated its Scottsdale Sanitary Sewer System plant on Sunday, October 25. Located on Miller Road south of Van Buren, the plant cost approximately $700,000 and went into operation in January 1959. It handled sewage for a 27-square-mile area.


On Aug. 7, the Scottsdale City Council approved the city’s participation in a proposed four-city sewage system, partnering with Phoenix, Tempe and Mesa. Approval of the system begins a 30-year program, costing Scottsdale $5 million. This is the precursor to the Sub-Regional Operating Group and the Arizona Municipal Water Users Association.


On June 3, the U.S. Supreme Court granted Arizona the entitlement to 2.8 million acre-feet of Colorado River water annually, nearly 20 percent of the river’s water, putting the state a step closer to realizing the long-awaited Central Arizona Project construction and implementation. This led to approval of the Colorado River Basin Project Act, in­cluding federal government construc­tion of the Central Arizona Project, on Sept. 30, 1968.


The Central Arizona Project enabling legislation is passed by the U.S. Congress, authorizing construction of a 330-mile-long canal from the Colorado River, through the Phoenix area and on to Tucson.


The Arizona Municipal Water Users Association (AMWUA) was incorporated by Scottsdale, Mesa, Phoenix, Glendale and Tempe. The purpose was to facilitate and advance municipal cooperation in securing and maintaining water and water rights for urban use.


March 15, Scottsdale purchased the Indian Bend Water Company for $2.7 million, commencing municipal operation of the water system. Serving about 15,000 persons, the purchase encapsulated four wells, about 57 miles of water mains, and an estimated 4,025 accounts and other storage facilities.


Construction began on the long-awaited Central Arizona Project (CAP) Canal.


Scottsdale purchased the Desert Springs Water Company from the Herberger family.


AMWUA negotiated an agreement with APS to provide reclaimed wastewater for cooling purposes at the Palo Verde Nuclear Generating Station. The reclaimed wastewater was treated by the 91st Avenue Wastewater Treatment Facility owned by the original five AMWUA members.


Scottsdale forms the Municipal Utilities Department which includes the administration and operation of the city’s water and sewer system.


The Sub-Regional Operating Group (SROG) was formed among several Valley cities, including Scottsdale, to operate a regional wastewater conveyance and treatment system. The plant supplies treated wastewater for multiple uses including the Palo Verde Nuclear Generating Facility, Tres Rios Wetlands and Buckeye Irrigation District.


Arizona Governor Bruce Babbitt signed the landmark Arizona 1980 Groundwater Management Act on June 12, mandating the proof of a 100-year assured water supply for new development to obtain the goal of “safe yield” by the year 2025 in the Phoenix Active Management Area. Safe yield achieves the balance between groundwater pumped and recharge in the aquifer both naturally and artificially.


The City purchased the Pinnacle Paradise Water Co. which had been established by developer Jerry Nelson in the early 1970s.


Trichloroethylene (TCE) was discovered in some Phoenix and Scottsdale water wells that served much of southern Scottsdale; seven wells were eventually shut down.


Scottsdale purchased the Pinnacle Peak and Ironwood Water Companies and started negotiations for the North Valley Water Company – all had been serving the newly annexed northern area of the city.


The Scottsdale Water Conservation Office is formed, managing rebate programs, home watering efficiency audits and water conservation education workshops.


Scottsdale acquired the North Valley Water Company.


The U.S. Environmental Protection Agency added a contained aquifer in south Scottsdale to the National Priority List establishing the North Bend Wash Superfund Site.


Markland Properties Inc. dedicated the Gainey Ranch Water Reclamation Facility, the first to return non-potable water for golf course irrigation.


Scottsdale City Council unanimously approved the transfer of the Gainey Ranch Water Reclamation Plant from its developer to the city. The plant is the first in Scottsdale designed to reclaim and treat wastewater.


Scottsdale’s $25 million Central Arizona Project water-treatment plant began operating in April and by July was pumping 7 million gallons of water a day into the city’s water system.


Scottsdale purchased the water system that served the southern part of Scottsdale from Phoenix. In the same agreement Scottsdale sold portions of the Ironwood and North Valley water service areas west of 56th Street to Phoenix.


Scottsdale opened its new Corporation Yard on Via Linda and dedicated its CAP water treatment facility.


Construction began on the North Indian Bend Wash Groundwater Treatment Facility to clean up the superfund site.


Scottsdale’s Reclaimed Water Distribution System (RWDS) became operational March 24. The $14 million system was one of the largest water development projects in the country devoted to the irrigation of golf course communities. Using reclaimed water for golf course irrigation allows Scottsdale to save an estimated one billion gallons of groundwater annually.


The $7 million North Indian Bend Wash Central Groundwater Treatment Plant went online, commencing the cleanup of the superfund site. This facility removes TCE from contaminated groundwater to a level that is considered non-detect and below EPA standard. This project is part of an agreement with the EPA requiring Motorola Inc., Siemens Corp. and SmithKline Beecham Corp. to construct and pay for a treatment plant to remove volatile organic chemicals from the groundwater.


Scottsdale City Council approved seven Central Arizona Project exchanges to add 17,800 acre-feet of water to Scottsdale’s CAP allocation.


Roosevelt Dam was reconstructed raising its height by 77 feet to 357 feet. This increased the water capacity by 20 percent. The City of Scottsdale participated in this project through funding in exchange for water space behind the dam.


The Scottsdale Water Campus started operations at the $116 million facility and was the largest public works project in city history to date which included: a 145-acre facility, a 70 million gallon per day drinking water treatment plant, a state-of-the-art water quality laboratory, a water reclamation plant, the world’s largest Vadose Zone groundwater-recharge well field and the world-renowned Advanced Water Treatment Plant.


The Scottsdale Water Campus celebrated its Grand Opening on Hualapai Drive. The $116 million facility was the largest public works project in city history to date which included: a 145-acre facility, a 70 million gallon per day drinking water treatment plant, a state-of-the-art water quality laboratory, a water reclamation plant, the world’s largest Vadose Zone groundwater-recharge well field and the world-renowned Advanced Water Treatment Plant.


Chaparral Water Treatment Plant was dedicated on January 9th. The facility was designed to treat 30 million gallons per day of raw water from the SRP Canal and distribute the drinking water to residents in South Scottsdale. Because the plant was constructed within a residential area, it was designed to share the neighborhood by surrounding the plant with architectural features, walking paths, public restrooms and a dog park.


Xeriscape Garden, a 5.5-acre demonstration garden, is open to the public providing an educational resource for growing native plants to reduce outdoor water use, foster development of sustainable landscaping and enlist community participation to conserve water resources for the future. The garden is a National Wildlife Federation Certified Wildlife Habitat and conceals a 5.5-million-gallon reservoir from the Chaparral Water Treatment Plant. The garden showcases over 7,000 plants from 200 species.


Scottsdale, along with four other valley cities (Glendale, Mesa, Phoenix, and Tempe) enter into a new Effluent Supply Agreement with Arizona Public Service Company, the Operating Agent of Palo Verde Nuclear Generating Station, to supply treated effluent. The agreement runs from 2010 through 2050 and reuses Scottsdale’s wastewater.


CAP III, at the Water Campus, expanded the water treatment plant to 70 MGD and included a new 10-MG finished water reservoir. The project also included a new pretreatment complex; a dissolved air filtration facility for pre-membrane treatment; and a new 22-MGD microfiltration facility with associated cleaning-in-place (CIP) systems, chemical storage area, air scour equipment, and electrical equipment.


Scottsdale Water commissioned the engineering of a centralized operations Control Room to monitor, evaluate and maximize all aspects of each system operated by Water Resources. This technologically advanced system creates faster response times to water breaks and outages, eliminates redundancy throughout facilities and improves system reliability. The Control Room also developed and implemented an integrated operating plan for all utility systems.


Construction was completed for a new treatment facility for the long-term remedy for the North Indian Bend Wash (NIBW) site. The NIBW Granulated Active Carbon (GAC) Treatment Facility extracts water from well PCX-1 and uses a liquid GAC treatment process to clean and treat the water. All costs are paid by the responsible parties.


Scottsdale Water partners with Phoenix, Glendale and Calgon Carbon to build a state-of-the-art Granular Activated Carbon (GAC) reactivation facility in central Arizona. The Calgon GAC reactivation facility lowered Scottsdale Water’s operating costs for GAC services by over $1 million a year while significantly lowering the city’s carbon footprint.


The Scottsdale City Council approved a rebate program to curb excess salt in wastewater caused by water softeners.


Scottsdale Water creates the Scottsdale Water Citizen Academy which is a five-week course that gives customers and stakeholders an in-depth look at all aspects of the water utility.


In October Scottsdale Water began using power generated at Hoover Dam after receiving the second largest municipal allocation in Arizona. The 50-year contract is expected to save nearly $3.9M in electrical power cost throughout the agreement.


As part of SROG, Scottsdale is part of the 91st Avenue Biogas Project which broke ground to clean the methane discharged from the solids processing at the treatment plant.


Scottsdale’s Water Dept. celebrated the 20th anniversary of its Water Campus with a public open house on Oct. 17, 2018.


In September, Scottsdale’s Advanced Water Treatment Plant at the Water Campus became Arizona’s first permanent water treatment facility permitted to treat recycled water for potable water uses; one of only three such facilities in the U.S.


The U.S. Bureau of Reclamation’s WaterSMART Water and Energy Efficiency program awarded Scottsdale Water a $1.5 million grant to support the city’s long-term water supply sustainability program. Money will be used to construct its aquifer storage and recovery well field project, enabling the city to recharge a portion of its Colorado River surface water allocation into aquifers within the city’s service area.

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Scottsdale Water Resources

9312 N. 94th St. Scottsdale, AZ 85258


Monday 7 a.m. - 4:30 p.m.
Tuesday 7 a.m. - 4:30 p.m.
Wednesday 7 a.m. - 4:30 p.m.
Thursday 7 a.m. - 4:30 p.m.
Friday 7 a.m. - 4:30 p.m.
Saturday Closed
Sunday Closed
City Holiday Schedule
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